Boy thomas



Patented Sept. 6, 1932 r ROY-THOMAS, F nos ANGELES, CALIFORNIA oner-'1 I Application filed April 2,

This invention relates to that type of torch which produces intense heat through combustion by the aid of free oxygenof a gas containing either orboth'carbon and hydrogen, acetylene being the combustible gas generally employed andthe inventior being therefore hereinafter described with particular reference to an oxyacetylene torch. I

It is an object of the invention to so control flash-back in the'torch as to eliminate all danger the'r'efrom,and moreparticularly to provide a control which will function irrespectiye of the relative pressures of the oxygen and acetylene, and which comprises an extremely simple'and readily manufactured construction requiring no'replacement or adjustment. i

It is a further object of the invention to' provide a flash-back control which will also function to stabilize the flow'of the" gases which produce the combustible mixture, so as to insure proper combustion and'a flame of maximum efficiency'. p

More particularly it is an object of the invention to. provide an abrupt lateral offset in a supply bore which leads to the mixing chamber of the torch, so'that in the event of flash-back beyond the mixing chamber and into said bore, the flame propagation'by inrpinging squarely against the solid abutment surface formed by the lateral offset will re bound and be so retarded that the velocity of the gas being supplied through the bore to 85 the mixing chamber will arrest further rearward travel of the flame, and will thus extinguish the fire through lack of the presence at said point in the supply bore in rear of the mixing chamber of the necessary combination of both. oxygen and combustible gas for supporting combustion.

- It is a further particular object of the invention to preferably arrange the lateral ottset so as to form a restriction in the supply bore for stabilizing the flow of gas therethrough prior to its discharge into the mixing chamber, in order to insure a uniform, P

combustible mixture and consequent maximum efficiency of combustion.-

It is a still further object of the invention to preferably provide such a lateral offset in 1929. Serial no. 351,911.

rear of the mixing chamber in each of the oxygen and the acetylene supply bores, 311 though onlysuchoifset iii-the acetylene bore is essential; and if said ofl'sets are provided inboth the acetylcneand the oxygen :bores they preferably each form an appreciable restriction for stabilizing both the oxygen and the combustible gaspriorto their intermix ing for formingthe combustible mixture. I Further objects of-theinvention will be readily understood from the following description of the accompanying drawing, in which: g

Fig. 1 is aside elevation, partly in axial section, of a torch constructed in accordance with the invention.v v

'Fig. 2 is-a detail fragmentary transverse section on the lineQ-Q of Fig. l. 1

Fig. 3 is a detail side elevation, partly in axial section, of ahead-for a torch embodying the invention and showing a modified construction. 1 v 7 Fig l is a detail fragmentary transverse section on the line -il4 of Fig. 3.

Fig. 5 is a View similar to Fig. 3 but show- 7; ing a still further modification.

Fig. 6 is a detail fragmentary transverse "section on the line 66 of Fig 5.

The invention may be embodied in any torch adapted toburn a combustible mixture of a gas such as acetylene-and an oxidizing agent such as pure oxygen; and is herein described in connection with a usualoxyacetylene welding torch wherein ahead 1 has supply bores 2 and 3 for acetylene and oxygen 35 respectively, and a mixer 4 which is mounted on the head and is adapted to form alcombustible mixture of the oxygen and acetylene, with the combustible mixture adapted top'ass through a usual gooseneck 5 to a burner tip 9 6. Acetylene and oxygen are-preferably respectively supplied to bores 2-3 through tubes 7 and 7. which are suitably fixed to the rear end of head 1 and maybe enclosed in a handle 8, and the acetylene and oxygen sup- O6 ly are separately regulated by usual valves 9 and ,9 for the respective tubes 7 and 7 In the eventof flash-back, if the flame travels rearwardly beyond mixer 4 it enters bores 2 and 3 which are so arranged as to arrest '10.

' rparward propagation of the flame and .thus

extinguish the fire through absence in either of said bores of the necessary mixture of acetylene and oxygen for supporting combustion,

and this arrangement of the bores whereby flame propagation is arrested preferably also" ment will cause its rebound andso arrest its travel that the velocity of the rearwardly' traveling flame will be exceeded by that of the acetylene being supplied in the opposite direction through' the bore, and the flame will thus be arrested at the lateral offset in the bore and will consequently be extinguished through the absence in said bore of the oxygen necessary to support combustion.- The oxygen bore 3 is shown as provided with a similar lateral offset for arresting flame propagation, although the arresting of rearward travel of the flame through the acetylene bore 2 is that which is essential for eliminating dangerous consequences from flash-back.

The lateral offsets in bores 2 and 3 may be provided as shown in Figs. 1 and 2, wherein the major lengths of said bores are drilled straight into head 1 from its rear end andat the desired inclination for alinement of the discharge ends of said bores with the mixer 4, and said discharge ends of the bores 2-3 which are shown at 10-11, respectively, are drilled into head 1 from its front end, with the bores 2-10,and 3-11 of preferably the same diameter and having parallel but nonconcentric axes whereby said bores 2-10 and 3-11 do not concentrically aline but par tiallyoverlap so as to form right-angled solid abutment shoulders 12-13 projecting into bores 10 and 11 where they meet the bores '2 and 3;

Flame propagation traveling rearwardly through bores 10 and 11 will thus forcibly strike the abutments 12-13 and will be subjected to a shearing action when tending to follow the abrupt lateral offsets and enter themajor lengths of thebores 2-3, and the flame will th'us be arrested so that the velocity of the acetylene and oxygenbeing supplied through bores 2-3 respectively, will prevent further rearward travel of the fire which will consequently be extinguished in the respective bores through the presence in'each of the same of only one of the component elements, acetylene and oxygen, the-mixture of which is necessary to support combustion.

The same result may be accomplished by the modified construction shown in Figs. 3 and 4, wherein head 1 is provided with an oxygen bore 3 which may have a laterally offset discharge end 11 as previously described: and the major lenth of the acetylene bore comprises a plurality of restricted bores 2 in close juxtaposition and communicating at their rear ends with the acetylene supply tube 7 as previously described, with a bore 10 drilled into the front end of head 1 so as to form the acetylene discharge to the mixer, and having its axis parallel to those of bores 2 and concentric with themedial )oint between the said bores 2, and being of a diameter whereby its cross-sectional area will completely overlie the cross-sectional areas of the plurality of bores 2' as shown in Fig. 4. Flame traveling 'rearwardly through bore 10 will thus strike the abutment shoulder 12' which is formed by the reduced cross-sectional areas of bores 2, and the flame will thus be arrested and its path of travel will be subjected to abrupt lateral offset and a shearing action as previously described.

A still further modification for accomplishing the same result is shown in Figs. 5 and 6, wherein the bores 2"-3 are drilled into the head 1 from its rear end as reviouslydescribed, and bores l( )"-11 0 respectively corresponding diameter are drilled into head 1" from its front end, with the respective bores 21-10 and 3"- 11 preferably having axes which are parallel but so .nonconcentric that the respective bores 2 and 10 and 3 and 11" just fail to even partially overlap as shown in Fig. 6. Transverse bores 15-16 are drilledinto head 1 from its opposite sides so as to respectively open the bores 2 -10 and 3"-11 to one another along the lateral bores 15-16, and plugs 17 are then inserted in bores 15 and 16 so as to close the outer ends of said bores laterally beyond bores 2 -3", thereby providing abruptly laterally offset paths of travel along the respective bores 10"-15-2 and 11 -16-3", so that the transversely projecting abutment shoulders 12 and 13" which are formed in said laterally offset paths of travel will arrest rearward flame propagation as previously described.

The lateral offsets in the supply bores of the head of the torch may also form restrictions in said bores which will tend to stabilize flow of the gases to the mixer 4. Thus for example with the construction shownin Figs. 1 and 2, the partial overlapping of bores 2-10 and 3-11 reduces the cross-sectional areas ofthe flow of gases at the junction of bores 2-10 and 3-11 as shown in Fig. 2, and then immediately re-expands the crosssectional areas of the flow to that-which has prevailed throughout the lengths of bores 2-3; and with the construction shown in Figs. 3 and 4 the cross-sectional area of the flow of acetylene is similarly reduced throughout the length ofrestricted bores 2, and is then re-expanded in bore 10 to sub stantially that cross-sectional area of .flow

which is supplied through the acetylene tube 7. In similar manner the change in direction of the flow through the transverse bores 15 and 16 as provided for in the construction shown in Figs. 5 and 6, will act the same as restrictions in the cross-sectional areaof the bores f r the purpose of stabilizing the flow for stabilizing flow of the gases to the mixer.

in order to insure a combustible mixture of maximum efiiciency.

I claim:

1. In a torch of the character described, a mixer, a head having a supply bore communicating with the mixer. the said bore having an abrupt lateral ofiset adapted to arrest flash-back rearwardly beyond the mixer and into said bore. P

2. In a torch of the character described, a mixer, a head having a supply bore communicating with the mixer, the said bore having an abutment projecting into said bore and adapted for impingement by'fiame propagation rearwardly beyond the mixer andinto said bore.

3. In a torch of the character described, a mixer, a head having a supply bore communicating with the mixer, the said bore having a restrict on therein rearwardly from the mixer, with the cross-sectional area of said bore substantially the same in both directions beyond the restriction.

4. In a torch of the character described, a mixer, a head having a supply bore communicating with the mixer, the said bore having an abrupt lateral oifset rearwardly from the mixer and forming an abutment projecting into said bore and adapted for impingement by flame propagation rearwardly beyond the mixer and into said bore.

5. In a torch of the character described, a mixer, a head having a su ply bore communicating with the mixer, t e said bore having an abrupt lateral ofi'set forming a restriction in said bore rearwardlyfrom the mixer, with said lateral oflset adapted to arrest flash-back rearwardly beyond the mixer and into said bore.

6. In a torch of the character described, a

mixer, a head having a supply bore communicating with the mixer, the said bore having an abrupt lateral offset rearwardly from the mixer and foriningan abutment projecting into said bore and adapted for impingement by flame propagation rearward] beyond the mixer and into said bore, the a rupt lateral offset also forming'a restriction in the said bore;

the mixer, saidbores each having an abrupt lateralgofl'set adapted to arrest "flash-back rearwardly beyond the mixer and into said bore.

8. In a torch of the character describctha mixer, a head' havin bores for supplying a combustible as an an oxidizing agent to the mixer, sai bores each having an abut- 7. In a'torch of the character described, a mixer, a head havingbores for, supplying a' combustible gas and an oxidizing agent to ment projecting into said bore and adapted I for impingement by flame propagation rearwardly beyond the mixer and'into said bore.

9. In a torch of the character described,-a mixer, a head having boresfor supplying a combustible gas and an oxidizingagont' to the mixer, said bores each having a restriction therein rearwardly from the mixer.

10. In a torch of the character described,

a mixer, a head having a supply bore communicating with the mixer, the said bore having the axis of'its discharge end parallel to but so non-concentric. with the axis of its supply end that saidvends of the bore comniunicate by onlya partial overlapping.

11. In a torch of the-characterdescribed, a mixer, a head having bores for supplyin a combustible gas and an oxidizing agent to't e the mixer, said bores each having the axis of its discharge endparallel to but so non-concentric with the axis of its supply end that said ends of the bore communicate by only a partial overlapping.

12. In a torch of the character described,

Walls forming a mixing chamber having- .a supply bore communicating with said mixing chamber, said bore having an abutment projectin into said bore in a position to arrest flashiack in said bore.

14. In a torch of the character described, walls forming a mixing chamber having communication with a burner, and walls formin bores for supplying a combustible as an an oxidizing a ent to said mixing chamber, said bores eac h havin an offset therein adapted to arrest flashack rearwardly beyond the mixing chamber and into said'bor'es.

15. In a torch of the character described,

walls forming a mixing chamber having communication with a burner, and walls forming bores for supplying a combustible gas and an oxidizing agent to said mixing chamber, said bores each having an abutment projecting I thereintofor arresting flash-back therein.

16. In a torch of the character described, the combination of: a mixer; and a member having a supply passage communicating with said mixer, said supply passage including two portions oiiset on'a plane substantially normal to their axes for arresting flash-back.

17 In a torch of the character described, the combination of a mixer; and Walls forming passages communicating with said mixer, at least one of said passages including two portions ofiset relative to each other and providing an abutment. adapted for impeding flame propagation ast said abutment.

18. In a torch o the character described, the combination ofz'a mixer; a member having a supply passage communicating with said mixer; and an abutment attached to said member and extendin into said passage substantiall normal to 518 axis thereof for impeding ame propagation through said pa ssage.

19. In a torch of the character described, the combination of: walls forming a mixing chamber; and walls forming a combustion support-ing gas passage and a combustible gas passage, said combustible gas passage including two portions offset to provide a shoulder adapted for impingement by flame propagation rearwardly beyond the mixing chamber. 1

In testimony whereof I have afiixed my signature. g a

: ROY THOMAS. 

